from django.db import models

from django.contrib.auth.models import User

# 在这里创建模型。

class Topic(models.Model):
	"""用户学习的主题"""
	text = models.CharField(max_length=200)
	date_added = models.DateTimeField(auto_now_add=True)
	owner = models.ForeignKey(User, on_delete=models.CASCADE)

	def __str__(self):
		"""返回模型的字符串表示"""
		return self.text

class Entry(models.Model):
	"""学到的有关某个主题的具体知识"""
	topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
	text = models.TextField()
	date_added = models.DateTimeField(auto_now_add=True)

	class Meta:
		verbose_name_plural = 'entries'
	def __str__(self):
		"""返回模型的字符串表示"""
		if len(self.text) > 50:
			return f"{self.text[:50]}..."
		else:
			return self.text
		